输电塔线体系抗风设计理论与发展
摘 要:输电塔线体系是国家重要的电力工程设施。显然,它们的安全性直接关系到国家电网运行的可靠性,而
风荷载是影响它们安全性的主要因素之一。首先,简要介绍了我国超高压、特高压输电线路的发展前景。接着,从输电塔
线体系的分析模型、动力特性、风致动力响应、风致振动控制等几个方面,对输电塔线体系抗风设计理论的发展进行了综
述。最后,论文重点阐述了输电塔线体系抗下击暴流风荷载设计的重要性,提出了有待于研究的若干问题。指出了对下
击暴流风荷载的研究将为我国建造模拟雷暴风环境的新一代风洞实验室和输电塔线体系的抗下击暴流提供理论基础和
设计指导,同时为输电塔线体系的风致振动控制设计与实现提供重要的参考。
主动多重调谐质量阻尼器
By resorting to Fourier transform, the equations of motion for the soil-asymmetric structure-active
multiple-tuned mass dampers (AMTMD) interaction system are developed in the frequency domain under
the ground acceleration. The criterion for searching the optimum parameters of the AMTMD is selected as
the minimization of the minimum values of the maximum displacement dynamic magnification factors
(DMF) of the asymmetric structure with the AMTMD. The estimation criterion of the effectiveness of the
AMTMD is chosen as the ratio of the minimization of the minimum values of the maximum displacement
DMF of the asymmetric structure with the AMTMD to the maximum displacement DMF of the
asymmetric structure without the AMTMD. Employing these two criteria, the parametric studies for the
influences of the normalized eccentricity ratio (NER), torsional to translational frequency ratio (TTFR),
stiffness ratio of the soil relative to the structure.
主动多重调谐质量阻尼器的参数研究
The application of active multiple tuned mass dampers (AMTMD) for suppressing
translational and torsional responses is addressed for a simplified two-degree of
freedom structure, able to represent the dynamic characteristics of general
asymmetric structures subject to ground motions. By employing the developed
optimum parameter and effectiveness criteria of the AMTMD, the influences of
the normalized eccentricity ratio and the torsional-to-translational frequency
ratio of asymmetric structures on the optimum parameters and effectiveness of
the AMTMD are investigated in detail. For comparison purposes, the results of a
single active tuned mass damper also are taken into consideration
半刚性连接钢框架-钢板剪力墙结构抗震性能试验研究
通过对半刚性连接框架-钢板剪力墙结构在水平反复荷载作用下的试验研究,得到了结构的滞回曲线、延性指标、水平
刚度、梁柱应变、转角及各关键部位的变形。从耗能能力、刚度退化、承载力、延性等方面分析该种结构的抗震性能和耗能
机理;依据应力分布、梁柱转角研究半刚性节点与钢板剪力墙的相互影响效果;分析结构的内力转换和破坏模式。结果表
明:该结构具有良好的延性和耗能性能;半刚性节点在反复荷载作用下没有明显变形,节点刚度退化小,框架和钢板剪力墙
协同工作良好;梁柱半刚性连接弱化了结构的整体刚度,框架自身承担的水平荷载有限;破坏模式为内填钢板剪力墙局部
撕裂,拉力带作用明显,钢框架柱脚及梁柱半刚性连接部位形成塑性铰,框架整体呈弯曲破坏模式。